"... Research into the cognitive aspects of programming originated in the study of professional programmers (whether experts or students). Even "end-user" programmers in previous studies have often worked in organizations where programming is recognized to be demanding professional work- the te ..."

Research into the cognitive aspects of programming originated in the study of professional programmers (whether experts or students). Even &quot;end-user&quot; programmers in previous studies have often worked in organizations where programming is recognized to be demanding professional work- the term &apos;vower-user&quot; recognizes this technical kudos. But as personal computers become widespread, and most new domestic appliances incorporate microprocessors, many people are engaging in programming-like activities in domestic or non-professional contexts. Such users often have less motivation and more obstacles to programming, meaning that they may be unlikely even to take the first steps. This paper analyses the generic nature of those first steps, and identifies the cognitive demands that characterize them. On the basis of this analysis we propose the Attention Investment model, a cognitive model of programming that offers a consistent account of all programming behaviour, from professionals to end-users.

"... Constraints and dependencies among the elements of embodied cognition form patterns or microstrategies of interactive behavior. Hard constraints determine which microstrategies are possible. Soft constraints determine which of the possible microstrategies are most likely to be selected. When selecti ..."

Constraints and dependencies among the elements of embodied cognition form patterns or microstrategies of interactive behavior. Hard constraints determine which microstrategies are possible. Soft constraints determine which of the possible microstrategies are most likely to be selected. When selection is non-deliberate or automatic the least effort microstrategy is chosen. In calculating the effort required to execute a microstrategy each of the three types of operations, memory retrieval, perception, and action, are given equal weight; that is, perceptual-motor activity does not have a privileged status with respect to memory. Soft constraints can work contrary to the designer&apos;s intentions by making the access of perfect knowledge in-the-world more effortful than the access of imperfect knowledge in-the-head. These implications of soft constraints are tested in two experiments. In experiment 1 we varied the perceptual-motor effort of accessing knowledge in-the-world as well as the effort of retrieving items from memory. In experiment 2 we replicated one of the experiment 1 conditions to collect eye movement data. The results suggest that milliseconds matter. Soft constraints lead to a reliance on knowledge in-the-head even when the absolute difference in perceptual-motor versus memory retrieval effort is small, and even when relying on memory leads to a higher error rate and lower performance. We discuss the implications of # Supplementary data associated with this article can be found, in the online version, at doi:10.1016/ j.cogsci.2003.12.001 ## An earlier, much simpler version of this report was presented as an eight-page conference paper at CHI2001. That paper is archived as Gray and Fu (2001).

"... The ready availability of online source-code examples has fundamentally changed programming practices. However, current search tools are not designed to assist with programming tasks and are wholly separate from editing tools. This paper proposes that embedding a task-specific search engine in the d ..."

The ready availability of online source-code examples has fundamentally changed programming practices. However, current search tools are not designed to assist with programming tasks and are wholly separate from editing tools. This paper proposes that embedding a task-specific search engine in the development environment can significantly reduce the cost of finding information and thus enable programmers to write better code more easily. This paper describes the design, implementation, and evaluation of Blueprint, a Web search interface integrated into the Adobe Flex Builder development environment that helps users locate example code. Blueprint automatically augments queries with code context, presents a code-centric view of search results, embeds the search experience into the editor, and retains a link between copied code and its source. A comparative laboratory study found that Blueprint enables participants to write significantly better code and find example code significantly faster than with a standard Web browser. Analysis of three months of usage logs with 2,024 users suggests that task-specific search interfaces can significantly change how and when people search the Web.

"... Soft constraints hypothesis (SCH) is a rational analysis approach that holds that the mixture of perceptual-motor and cognitive resources allocated for interactive behavior is adjusted based on temporal cost-benefit tradeoffs. Alternative approaches maintain that cognitive resources are in some sens ..."

Soft constraints hypothesis (SCH) is a rational analysis approach that holds that the mixture of perceptual-motor and cognitive resources allocated for interactive behavior is adjusted based on temporal cost-benefit tradeoffs. Alternative approaches maintain that cognitive resources are in some sense protected or conserved in that greater amounts of perceptual-motor effort will be expended to conserve lesser amounts of cognitive effort. One alternative, the minimum memory hypothesis (MMH), holds that people favor strategies that minimize the use of memory. SCH is compared with MMH across 3 experiments and with predictions of an Ideal Performer Model that uses ACT-R’s memory system in a reinforcement learning approach that maximizes expected utility by minimizing time. Model and data support the SCH view of resource allocation; at the under 1000-ms level of analysis, mixtures of cognitive and perceptual-motor resources are adjusted based on their cost-benefit tradeoffs for interactive behavior.

"... Explicit information-seeking actions are needed to evaluate alternative actions in problem-solving tasks. Information-seeking costs are often traded off against the utility of information. We present three experiments that show how subjects adapt to the cost and information structures of environment ..."

Explicit information-seeking actions are needed to evaluate alternative actions in problem-solving tasks. Information-seeking costs are often traded off against the utility of information. We present three experiments that show how subjects adapt to the cost and information structures of environments in a map-navigation task. We found that subjects often stabilize at suboptimal levels of performance. A Bayesian satisficing model (BSM) is proposed and implemented in the ACT-R architecture to predict information-seeking behavior. The BSM uses a local decision rule and a global Bayesian learning mechanism to decide when to stop seeking information. The model matched the human data well, suggesting that adaptation to cost and information structures can be achieved by a simple local decision rule. The local decision rule, however, often limits exploration of the environment and leads to suboptimal performance. We propose that suboptimal performance is an emergent property of the dynamic interactions between cognition and the environment.

"... Abstract. The paper discusses some significant issues in the empirical evaluation of interactive recommender: the role of experiments, the contingent and constructive nature of users ’ interaction strategies, and the generalizability of the results. We propose to adopt as the main evaluation goal th ..."

Abstract. The paper discusses some significant issues in the empirical evaluation of interactive recommender: the role of experiments, the contingent and constructive nature of users ’ interaction strategies, and the generalizability of the results. We propose to adopt as the main evaluation goal the construction of a situation-specific account of the user-system behavior, and we suggest applying the context matching approach to cope with the contingencies of the user behavior. To make clear the limitations of high-level single step experimental evaluations, we present a critical analysis of a case study, a pilot evaluation of a travel recommender system (ITR). The examination of this study shows the danger of overlooking the detailed aspects of user-system interaction, and underlines the need to iteratively refine the evaluation hypotheses and design when no detailed model of the user-system behavior is initially available.

"... Successful problem solving depends on a dynamic interplay of resources between agent, task, and task environment. To illuminate these interactions we studied how participants added a series of single-digit numbers presented on a computer screen. We distinguished between four different user inte ..."

Successful problem solving depends on a dynamic interplay of resources between agent, task, and task environment. To illuminate these interactions we studied how participants added a series of single-digit numbers presented on a computer screen. We distinguished between four different user interfaces, each implementing a different mode of interaction with the displayed addends: look only, point, mark, and move. By collecting and analysing complete interaction protocols we were able to integrate overall performance measures with fine-grained behavioural process data on the strategies engendered by the different user interfaces. We discovered reliable differences in the chosen sequences of addends, which can be understood in terms of the cost-benefit structures provided by the interactive resources of the user interfaces.